package com.itheima.reggie.filter;

/*
 *   检查用户是否已经登录
 * */

import com.alibaba.fastjson.JSON;
import com.itheima.reggie.common.BaseContext;
import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 拦截器
 */
@Slf4j
@WebFilter(filterName = "loginCheckFilter", urlPatterns = "/*")
public class LoginCheckFilter implements Filter {
    //路径匹配器，支持通配符
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();


    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        //1.获取本次请求URI
        String requestURI = request.getRequestURI();

        log.info("拦截到："+requestURI+"路径请求");

        //定义不需要处理的路径
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/common/**",
                "/user/sendMsg",
                "/user/login"
        };

        //2.判断此次请求是否需要处理
        boolean check = check(urls, requestURI);

        //3.如果不需要处理，则进行放行
        if (check){
            log.info("本次请求不需要处理");
            filterChain.doFilter(request, response);
            return;
        }

        //4-1.判断浏览器端登录状态，如果已经登录则放行
        if (request.getSession().getAttribute("employee") != null){
            log.info("用户已登录，用户id为：{}",request.getSession().getAttribute("employee"));

            //获取当前用户登录的id
            Long empId = (Long) request.getSession().getAttribute("employee");
            //设置ThreadLocal变量id
            BaseContext.setCurrentId(empId);

            filterChain.doFilter(request, response);
            return;
        }

        //4-2.判断移动端登录状态，如果已经登录则放行
        if (request.getSession().getAttribute("user") != null){
            log.info("用户已登录，用户id为：{}",request.getSession().getAttribute("user"));

            //获取当前用户登录的id
            Long userId = (Long) request.getSession().getAttribute("user");
            //设置ThreadLocal变量id
            BaseContext.setCurrentId(userId);

            filterChain.doFilter(request, response);
            return;
        }

        log.info("用户未登录");
        //5.如果未登录则返回未登录结果，通过输出流的方式向客户端页面响应数据
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;

    }

    /*
    *   路径匹配，检查此次请求是否需要放行
    * */
    public boolean check(String[] urls,String requestURI){
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestURI);
            if (match){
                return true;
            }
        }
        return false;
    }
}
